Java Web请求转发与重定向

①创建Servlet1 和Servlet2的Java文件

package zhuan;

import java.io.IOException;

import javax.servlet.RequestDispatcher;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

@WebServlet(value="/aaa")
public class Servlet1 extends HttpServlet{
	@Override
	protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
		
		//获取前台传过来的信息
		String username = req.getParameter("username");
		System.out.println(username);
		
		
		RequestDispatcher requestDispatcher = req.getRequestDispatcher("/servlet2");
		
		requestDispatcher.forward(req, resp);
		
	}
	@Override
	protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
		doPost(req, resp);
	}
}

package zhuan;

import java.io.IOException;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

public class Servlet2 extends HttpServlet{
	@Override
	protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
		System.out.println("我是Servlet2");
	}
	@Override
	protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
		doPost(req, resp);
	}
}

②配置web.xml文件

    Servlet1
    zhuan.Servlet1


    Servlet1
    /servlet1

	


    Servlet2
    zhuan.Servlet2


    Servlet2
    /servlet2

 请求重定向的两种方式：

方式一：设置响应头

resp.setStatus(302);
resp.setHeader("Location", "/response2");

方式二：使用servlet提供的ap(推荐使用)

resp.sendRedirect("response2");